Appendix — The anatomy of a brain

The body appendix drew the two lists: what comes in, what goes out. This page opens what sits behind them. The chapters meet the brain one part at a time (the rival guessers in chapter 6, wanting in chapter 9, the snapshot in chapter 11, taught steps in chapter 16); here the parts share one picture, because a question keeps arriving in different clothes: when the brain knows something, where does that knowledge live?

Everything inside the outline obeys two rules. Nothing in there is ever finished: every part keeps learning for as long as the brain runs. And nothing gets in from outside except through the senses. There is no side door where facts are loaded into the brain the way an app loads a database. Whatever it knows, it learned by living, and whatever it consults, it senses.

The parts

The frame store is the bulk of the brain: the population of small rival maps from chapter 6. Each frame is one guesser. It recognizes a slice of the world, predicts what that slice does next under each act, and is graded on nothing else. Frames are born when an observation fits no one and evicted when they stop earning their keep. What the store holds is habits rather than facts: how each corner of the world answers each poke.

The event head is one map more, with a different question. The frames ask “where am I”; the head asks “what will this act change”. Chapter 14 ran on it, because wanting follows expecting and the head is the expecting. It became brain state proper on 2026-08-09, snapshotted and resized with everything else.

The motivation layer is not a store at all. It is the brain’s posture this moment: how strong the itch to finish is, whether a commitment is alive, how loud a teacher’s label rings, how hungry the body is and how far that hunger may bend the vote. Yesterday’s posture is gone; only its consequences remain, in what the frames learned while it held.

Recipe memory is the exception, and the reason this page exists. When a demonstration teaches the brain a chain (chapter 16: the steps, not the ingredients), the steps are kept in their own structure, next to the frames rather than dissolved into them. It is the closest thing inside the brain to a bookshelf. Knowledge you can point to, carried as itself, grown only by teaching.

Where knowledge lives

So the honest split: inside the brain live skills, expectations, and one small shelf of taught steps, all plastic, all in chapter 11’s snapshot. Facts prefer to live outside.

The palate is the shipped example. What food is worth is a fact about the world, and the brain does not store it. The body keeps a little price book at the seam, written by nothing but meals: on 2026-08-10 a brain whose book was born all zeros ate its way to gem 1.000 and crystal 0.100, the world’s actual prices, with nobody ever telling it a number. The brain reads that book the only way it reads anything, as a sense. Copy the file and a different brain can taste with it.

I like this split for an engineering reason, not a philosophical one. A learner whose facts live in artifacts can have those facts inspected, corrected, and handed to the next brain without touching the thing that learned them. The frozen models of chapter 1 melt knowledge and skill into the same weights, which is why updating one risks the other; here the seam keeps them apart.

The same week supplied the warning that guards the rule. A brain whose wealth sense counted items could not learn a trade that loses count but gains worth: zero successes in twenty-four attempts. Pointing the same sense at worth instead flipped it to twenty-four of twenty-four (2026-08-10, both readings). Which sense defines a thing decides what the brain can know about it. An outside store is never a free lunch: the sense that reads it is a design decision, and consulting it well is a skill the brain has to be taught, like any other chain.

Under the hood: the zones, exactly. Verified against the running code and design 0018 on 2026-08-18, not copied from prose.

zone	in the code	holds	snapshotted
frames	FrameStore / FrameGroup	encoder, decoder, per-act transition per frame; born on demand, evicted by the survival score	yes
event head	owned by FrameStore	one per-act observation-delta model; off by config, bit-exact	yes
motivation	CompletionItchPolicy and its recipe subclass	the live itch, a held intention, label gain, deficit scaling	yes
recipe memory	RecipeMemory	taught step chains and their labels	yes
palate	PALATE_FILE, body side	learned prices, a running average of felt meals	body state: a portable file, sensed as the worth channel

The dials in the drawing (κ the itch, β the label, κ_d the deficit coupling, κ_c commitment) are specified in the record’s design 0011; each defaults to the measured operating point of design 0015. The snapshot carries every row above except the palate, which travels as its own file precisely because it is not brain.